The present invention relates to a quick connector for a multi-conductor circuit. Quick connectors for multi-conductor circuits, both in the form of flexible printed circuits and flexible multi-core cables, are known. A known type of connector for flexible printed circuits includes a longitudinally hollow parallelepiped base having a plurality of side-by-side seats whose center-to-center distances equal the distances between centers of the printed circuit tracks. Each seat includes an electrical contact which extends below the base in the form of a terminal for connection to the printed circuit board to which the connector is fitted. In order to clamp the flexible printed circuit to the connector, the stripped end of the printed circuit is inserted into the longitudinal cavity of the base, and is then locked by the insertion of a cover which performs the dual function of mechanically locking the printed circuit to the connector, and of laterally pressing its tracks against the contacts located in the various seats. The positioning of the cover relative to the base or block is made secure by snap projections present on the former and engageable with coacting recesses in the latter.
ln the above known connector, electrical contact between the printed circuit tracks and the contacts of the seats is insured by the spring configuration of the contacts, and mechanical locking against pulling is insured by teeth provided on the cover and engaging in holes in the printed circuit.
One drawback of this known connector is that the mechanical locking system is suitable only for flexible printed circuits, but not for multi-core cables.
A further drawback of this known connector is that each locking hole leads to the loss of one track of the printed circuit with the necessity to over-dimension it in order to insure the same capacity.
To overcome these limitations, it has been proposed to use special clamping devices by which mechanical locking is provided by the same elements which insure the electrical contact. These devices, which are suitable for the quick connection of both flexible printed circuits and multi-core cables, provided that the stripped ends of the latter are previously tinned, are of poor reliability because the mechanical locking elements can cut into or damage the electrical conductors.
If the conductor cover is hinged to the base, complete access to the inner longitudinal cavity of the base by the multi-conductor circuit requires the total opening of the cover, and consequently an overlying working space of sufficient height. Moreover, as the multi-conductor circuit leaves the connector "sideways" to the cover, the connector must be previously positioned in the board, this requiring special care during assembly.
A connector is also known having bores into which the previously tinned ends of conductors of a multi-conductor circuit are inserted, the ends then being immediately locked in position by a wedge cover. Again, in this case, each seat comprises an electrical contact which extends to the outside in the form of a prong or terminal to be soldered to the printed circuit board. One drawback of this connector is that each conductor is locked in its seat in a position corresponding with its sheath, and this does not insure perfect electrical connection, which is made even more uncertain by the fact that the contact is not of the self-cleaning type.
Another drawback is that the wedge clamping system requires a certain insertion force to produce mechanical locking, this requiring application of a large force to later disengage and separate the connector.
A further drawback is that the metal parts, conductor and contact, are pressed together by a rigid body which tends to make electrical contact uncertain, and is poorly adaptable to conductors of different sizes.
Finally, as in the case of the preceding connector, this last-discussed connector also requires the multi-conductor circuit connected to it to be positioned sideways, thus requiring its positioning relative to the printed circuit board.
Accordingly, the object of this invention is to obviate all of these drawbacks of the prior art, and effect a quick connection of the multi-conductor circuit without insertion force, with high electrical contact reliability independently of conductor diameter, and with secure locking against pulling and without restriction of its positioning on the printed circuit board.
This objective is attained according to the invention by a multi-conductor circuit connector which comprises:
a parallelepiped base provided with a longitudinal cavity divided into a plurality of seats of which the distance between centers is equal to the distance between centers of the conductors of the multi-conductor circuit;
a pair of springs for each seat connected to a terminal emerging from said base, at least one of the springs being elastically displaceable toward the other;
a cover snap-insertable into the longitudinal cavity of the base and provided for the introduction of the multi-conductor circuit with a central longitudinal slot bounded by two elastically yieldable ledges which approach each other on insertion of the cover into the base, and are arranged to retain the sheath of the multi-conductor circuit by clamping force, at least one of said ledges having means to cause the corresponding set of springs to approach the imposing set of springs of the connector.